Bug 1453032 - Part 1: Add a check in setSelectedNode to avoid reselecting the nodeFront if it is already selected. r=gl

MozReview-Commit-ID: 3ZafsNbpEPQ

--HG--
extra : rebase_source : 0771911346d262bedb5f8df5a5c036b3cf6d8118

devtools/client/inspector/animation/animation.js

@@ -355,6 +355,10 @@ class AnimationInspector {
   }
 
   async setSelectedNode(nodeFront) {
+    if (this.inspector.selection.nodeFront === nodeFront) {
+      return;
+    }
+
     await this.inspector.getCommonComponentProps()
               .setSelectedNode(nodeFront, { reason: "animation-panel" });
     await nodeFront.scrollIntoView();